Sintering machine



Oct. 2l, 1952 w, KELSEY 2,614,828

4 SINTERING MACHINE Filed March 2, 1950 2 Sl'iEETS-SHEET l INVENTOR. BY Wa/zr/Jfy 38 WM Oct. 21, 1952 W KELSEY 2,614-,828

SINTERING MACHINE Filed March 2, 1950 ypaw/ /ls Afro/MEV Patented Oct. 21, `1952 OFFICE `SINTERING MACHINE Walter Kelsey, New York, N. Y. ApplicationMarch 2, 1950, Serial No. 1H47,317

This invention relates tosintering machines and more particularly to improvements in `the inclined gravity acting type described in my copending application Serial No. 736,487, led March 22, 1947, for Gravity Flow Sintering Machines, U. S. LettersPatent No. 2,527,309 of October24,l95(). m i

The object of this invention isto provide such improvements and this invention consists essentially of Y a sinter pass inclined tothe vertical, having an open top in communication with the discharge outlet of a feed chute to receive `and carry the stockl in a line continuing in the direction of the feed chute discharge.. The inven- .tion consists further in providing means to` tilt the sinter pass to change its inclination to the vertical within the range of registration ofthe receiving opening ofthe sinter pass and the discharge conduit of the feed chute.

As a further alternative improvement, theinventionincludes Va `gravity flow inclined sinter pass with the lower surface of the sinter pass stepped at intervals for the breaking or shearing of the stock and sinter as it flows off each step. This continual stepping andshearing during the formation of the sinter, breaks `the sinter into pieces which are readily handled by a constant discharge device belowathe bottom endof the sinter pass, by which the speed` of the flow ofv sintermay be controlled, the controlling means operating inconsonance with the speed of flow of the stock desired in the sinter pass.

The invention also contemplates zan,.adjust able gate opening below the sinter passandbelow `this a controlledpaddle wheel sinter discharge. The invention also contemplates means to change the depth of the flow of the stock and the sinter in the machine. i i The sinter pass being variable in slope, the flow `of sinter stock and sinteris regulated in consonance with the sintering action, the top surface or side of the flowing sinter stock passing under an ignition device, to ignite the adjacent surface of the stock, andthe iiowof thestock with its ignited surface continues without change of-direction or reversal of slope through the` ythe machine is energized by gravity.` The slope of thesinteripass is such. as to produceiiowof the particular type of stock being utihzedregardless of resistances, the slope of .thesinter 4pass being capable of being `varedto accelerate sclaims. (omas-21) `thepivot 20is clearlyseen in Fig.` 1and isf, mbodied in both Figs. zandpreferml" or retard the flow- The machine is made so that the slope` as a whole can be` readily changedwto meet any changed condition, within the con` trolling rule that the inclination `of the. stock supporting Wall of the sinter pass must not be too steep but should retard but not prevent the flow of stock under the actionof gravity;

The function of this machine is to sinter ores, fly ash and to agglomerate any materials that can be so treated and put into condition `for iure ther use. i The sintering machines at present in use are elaborate and costly to build andlimited on that account in their scope oi' use. The present invention i'szsimple in design andconstruction, far less costly andaconsequently hasaxwider scope use. i' The invention will be further described, em bodiments thereof `shown in the drawings, and the invention will be finally pointed out in the claims. :j In the accompanying drawings, f i Fig. l is a side view outline drawing; showing provisions made for changing the slope `oi*' the sinter pass and showing supports Afor,1 the `sinter pass and frame shown in greaterzdetail in Fig. 2; Fig., 2` is a vertical section of a single sloping surface sinterypass taken `on line 2--2;j` of Fig. 5 is" a verticalsectionof a l,sloppass taken on line` fi-5U of i Referring generally to the drawings., both; em-

bodiments show a straight line flovvoi the stock from the discharge` end of the feeding chute to `the upper"v open receiving end of the `sinter@ass,

flow continuing Vwithout. reversal of thegslopeof `the stock, which sinter pass is sloped to permit gravity action to force the flow of stock, `butnct i retard the stock against such `gravity- ".action The tilting action voi the sinter pass `around slope of the sinter pass with respect to the horizontal is also shown in this Fig. 1.

The shearing steps 42 are shown in Fig. 5.

The shiftable opening for controlling the sinter flow in the sinter pass is shown in Figs. and 8.

More particularly, the inclosed stock feeding chute I0, (Figs. 2 and 5) and the offset inclosed stock feeding chute I4 have such a combined length between the gate II and the ignition chamber Il that-there is no appreciable loss of air suction or pressure through thestock held in the two air tight continuous connecting chutes. The stock lls the chutes throughout their crosssection area and forms an air choke. of the offset I2 is so sloped that the top of the owing stock is restrained, thus preventing the separation of large pieces in the stock during this part of the stock flow. The idea in these offset chutes with their stock pockets* Ita and Illa is to take the vertical stock load above each pocket and. break up theicompact Vcondition of thelstockas it flows out of each pressure relieving. pocket. l,Pocket Ita has. ahorizontal bottombutlonaccount of the Vslope changing provisionof the 'sinter pass the pocket Ifla has a sloping bottom formedsby the end of the sinter pass, which end has. an extension which may be joinedtoa part ofthe flange connection eX- tending from the feed chute. The top surface ofi stock in this variable sizeV pocket Ma has the same natural retarding slope as in pocket Ilia. Astheow ateach pocket is` created by the withdrawal' ofi-'stock-.from below, the. compact condition is thus greatly, reduced making the stock condition more open for .the passageof air. Two stock-pockets are shown in the drawings; it may be advisable to have more pockets to break up more completely the compact condition of stock and permit. afreer flow ofair through the stock. The-stock receiving' partZIa of the sinter pass has a top I3, not perforated, extending from a.

wall I5 to the ignition chamber Il, sloped at the naturalA freel slopeV of thetop of the stock, and abottom orgrate Ia extending from tl'e pocket I4a' beyondthe-ignitionchamber Il, in advance of the sinterpass proper 2| sloped. at the same 'slope of the sinter pass. lIn the embodiment, -thispart Illa which is agrateyandthe grate vof the sinter pass 2l are continuous (Fig. 2). n

"The stock feed chute' has for its object. to'prevent compacting of the stock, since thislwould prevent proper airingv of it,.for the subsequent sintering operation. At least, two steps are provided inr reverse direction to eachother', to divert the stock iiow angularly to the vertical and angularly to itself, and vertically spacedfrom each to allow for the continued stock flow. By providing pockets for the stock, the stock flows are guidedv by the surfaces Aof l.the stock in the-pockets, whereby intermingling of stock at these guiding Isurfaces ltake place. .While the embodiments shown, present the pocket walls I6 at' right angles tothe vertical wall adjacentA thereto, this -is` not essential, sincef acute or obtuse angular relationships -will operate tofcarry outthe princible, provided the guiding surface vhas an' angle tothe vertical which enables the stock toA iiow by-"gravity action, and be retarded, but noti prevented from flowing. The' flow ofthe stock, 'first 'in-one direction (angular infrespect'to" the' vertical) ,and then in the other, with a turning point between said directions, assures a fluiness 'to' the stock, v thus, preventing compacting yof the saine. VThroughout the feed chutthe stock extendszfromfwall to-wall, filling the horizontal ,4 cross-sectional areas from the receiving end of the chute to its discharge end. In the embodiments shown in Figs. 2 and 5, the feeding chute may be said to extend from its feed inlet valve II to about at the lower end of wall I3 forming a chute 2Ia with the part lila of the grate 23.

The sinter pass is made of a parallel top perforated surface wall 22 and bottom surface wall or grate 23 (Figs. l and 2), and inclosing side walls 24 (Fig. 3)', held `togetherin'a frame I9, pivoted on a shaft 2G (Figs.` l and'2). The grate 23. has a portion Illa which acts as the bottom of chute 2Ia. The top open end of the sinter pass 2l receives ignited stock from the lower side of the ignition chamber from chute 2Ia. The top 'end of the sinter pass chute 2Ia forms with the feed chute Ill a pocket Ita which varies in size depending on the slope position of the sinter pass.

Thus, the uppermost end ma of the grate 23 acts as the chute bottom and with the top I3 establishes the direction of the consequent stock flow with the sinter pass tilted tor provide a flow for that particular stock. The arrowsvldc point out.y the 'direction of the flow of stock atthat point. The next-adjacent part of the grate 23 'is opposite the ignition chamber wall I3, where the sinter pass proper 2l begins.

' The ignitionchaniber Il' (Figs. 2 and 5), is'v so made' as to burn the fuel used to aflame. The flame is impinged upon the exposed surface Ila ofthe sinter stock descending in the chute 2da throughout its width so as tovproperly ignite the stock while it passes (below. theA chamber Il. Any suitable ignition device may be used. :Air suction cr pressure at Illa aids to draw the name to the. surface of the stock. The intensityof the llame, theV width of the ignition chamber, the amount and rate of flow or stock, and the intensity of the air action, are individually-adjusted to give proper ignition to the surface of the 'stock passing the ignition device. The lower edge of side I8 of the ignition chamber is made to clearthe flowing ignited surface ofthe stock.

rrEhe angle of flow of sinter stock of any particular type by gravity is hard to Ipredict. The friction on the sinter pass surface varies with the weight, compactness and moisture content of the stockv with air pressure used and other variables. VThe angle of repose of the top surface is also variable `due to conditions mentioned and to the amount of formed sinter in the stock. A gravity flow sintering machinetomeet commercial conditions should be made with a range of.r slope for the sinter pass, and changes should be able to be easily made from slope to slope. For general use of the gravity iiow sintering ma- 'chine the depth of stock flow must be `made readily variable. This is provided for by chang- :ing the ychannelv `2da to a channel,` of "different depthusedk in building upv the enclosing sides 24 (Figs. 3 and 6), and adjustment in the chute closure pieces i3 and I5 (FigL'Z). For a sinteringv machine used constantly' for the same stock, the parts can be welded at 15a; orV suitableadjustable devices may be used for different stocks. Air duct 2l' and'ignition chamber I7 arejconnected to and move with a frame I9 and the pipying and duct. connections to'same (not shown) are made flexible or adjustable. Breaker roller 28 moves with the frame I9 and roller 29 is on the fixed `pivot and drive shaft Ztl (drive not ^3`z areI not moved withv the .changev of, slope; but

the walls'l and I5.l are adjustable as explained.

The sinter p-ass frame I9 (Fig. l) is supported by-`shaft 2 i) or othermeans on the fixed base havn ingparts 3l, 32, and 33 (Fig. 1), and by the ad" justing screw or other means at 34 at the tcp of may or may not be power driven (drive `not shown) `are supported from the inclosing sides 24 (Fig.` 3) and `the main supporting frame is -(Fig. l) shown in outline only. `Roller `35 is driven from shaft 2). This roller .-'l5vhas applied `to" its bottom side, a doctor or scraper 35 to remove adhering burning sinter allowing it to pass under the top 22 with the rest of the ignited sinter stock. The air for burning the sinterl passes `through the top 22,` through the sinter stock infthepass 2l and through the grate lila and grate 23 to the air duct 2 and to chimney duct connections `not shown. During the air passage through theignited stock `in the pass 2 I, the

ignited fire line 31 `is drawn through the flowing stock burning out against the grate 23 near the jlower part ofthe air duct 21.

I "The ysinter pass `2l is at an angleto the vertical and thefireline is at an angle to grate .23,

with constantly decreasing spaces from the grate `23; VThe angle of the .grate 23 to the Vertical, is such as to retardtheflow of the stock, but permit its llow under gravity action. l i

At the lower point "of the sinter pass 2l, all

the stock has been converted "to sinter and contlnuesto now down into the controlling sinter breaker `rollers 2B and 29.` These rollers control the stock flovvas in operation the stock gate Il at the top of the feed chute is open. The `length of the sinter pass from the bottornof the air `duct2'l vto thebreaker rollers 2t and l29 may be lengthened relatively beyond what` is shown to give space for the sinter to cool." This cooling "may 'beaided `by `a cross flow of cooling air.

Sinter is discharged from" the rollers on the con- Veyorril` and tothe conveyor 38 andto such :processing as reduireddischarging in the direc- ;tion ofthefarrows 30a. `The final discharge of sinter `or`1 stock from the single sloping sinter pass is controlled by the conveyor '39, as the free flowing stock is stoppedon this conveyor, and when "rernovedfacilitates the sinter flow from the sinter 'In Fig. 2 the sinter pass is also shownas rnovedV to 'a position at a lower slope which'is shown dotted. The topf is moved to position 22a, the guide roller 35110 position 35a, the ignition surface ller` to position 1lb, the grateia to positionY Ilia-side ofair duct 2l to position 2in, `top [of chuteV 1,3 to position itin and lbreaker rollerl 23 lto position 28a. Other features of the sinter pass and frame not named arernovedwith the 4frame to a position corresponding to the lower` flslope.4 A collecting conveyor-38 is shownto receive the sinter from conveyoril.

" ThesectionFig; 3` shows top guide roller 35 withrelation to the grateZ'J. and air 1- ductZl l and the constructionof the inclosine Sidealwithr i 6 provi-sionfor.` changing .helghttof` sanrie'lzby` chang@ ingdepth of' channels 24a. l

The `.section Fig;` 4 `shows the :crushingiioller 29am). shaft 2li (power connections notfshown) I in relationto thegpan conveyor 363.A .l

In Vanother embodiment, l, a: series '0f stepped grates are shown (Fig. `5). The sinter pass has a stepped perforated bottom surface or gratewhich extends from the stock inlet chute 2id :(Fig. `15)., to a space above the dischargextableorrloor '4H (Fig. 5). Thewall or step 4l is below the `wall i3, andthe ignition device (Figy5)".` Steps 42 follow downwardly in sequence. This succession of steps il and t2 are sloped to overcome:1 resistance and produce sinteristoek flowby. gravity action. About above theriser 45.0f eachtsteplis placed a` deflecting or pressure roller 43 `and 43a (power connection not shown)bearing cnythe surface of thestock in the sinterpass M and 44a forcing the new plastic sinter down ano" by pressure along line B9, for example, shearing theilow of sinter andstock at each riser Lib, this repeated shearing action on the stock and sinterfinwall stages of formation `resulting in producing separate pieces of sinter. The upper end of the fire line 35i starts at the ignition device andis pulled by the air iiow towardthelower side 421 and extinguished against the lowerside 42 near'lthe bottom of the air duct21.. This nre line orig nited surface 39 is broken at each shear point `but continues in the flow of stock tothe succeedwheel. This pressure wheel or'roller is subject to many variations to gain the working vcombination of pressure action and` air ow. With `a heavy sinter stock the weight of the stock mayfbe `sufficient to produce the shearing action without such wheels. A scraper 4S (Fig. v5), is applied as l maybe required to the pressure rollers 43 to keep `ignited sinter stock from building up on :the

rollers,` only one scraper d5 being shown. :The top surface of the flowing sinter is restrained by the perforated plates and d8. The step surn faces 4| and #l2 (Fig. 5) are built up'of grate bars but regardless of the step construction,` ,the face ofthe riser `llEi should be made offa `bar` for strength and `to stop off any air passage atA the risers to assure a good air flow` control `through the grates. Air and gases should .be permitted to leave the sinter pass only through the `openings in the step surfacesv of steps 4l and 42. The length of the bottom part alla of `the sinter pass from the bottom of vthe air duct `2i to the discharge table lil may belonger relativelythan is shown cn the drawing. The step and shearing feature will then extend'downwardly to beyond `the point, where the hot sinter cementstogether into a cake, below which point the steps` can `be omitted. This lengthening isyto give the ncwing sinter time tocool, which can be ,aided by a `cross flow of cooling air. l 7o The lower `end of the sinter passda` (Fig.,l5), discharges the broken sinter from under the lowerrnost roller 63a and lowermost riser bar 61 `between the sinter pass sides 54 (Fig. 8);, into a` free surfaced flowing` pile Stresting onthe discharge equalizirisl sate with, leaves 5.'.an i` 53x which are age-14,828

'onthe discharge table! 45. Thesetwo equalizing gate leaves are joined togetherby side pieces 6i! and header piece tv (Fig. 8), with an opening between the leaves and screws 65 for adjusting the gate opening. This really forms a gate valve with an adjustable'opening at the center. This equalizing gate valve opening is placed above the opening between the sinter pass Vsides in the .top ofv table 40 and adjusted for the desired flow of sinter from the pile 63 to the discharge pocket 5|, and moved so that the opening is in such a position in the pile '53 as `to direct the flow of sinter from the pile and from the sinter pass Mia -togive ra uniform mass flow through the whole cross-sectional area of the sinter pass Ma. The discharge pocket 5|v extending between the extended sinter. pass sides (Fig. 5), is air tight and deep enough so that the contained sinter will make an air seal pocket between the table i5 and the cutv off plate 55 at the top of the sinter discharge control wheel 55. This control paddle wheel 55 (Fig. 5) is set in what would be a free discharge from the pocket 5l, between the flow cut off plate 55 and the end 50 of the bottom 5l. `This wheel held rigid` intercepts and stops by'its paddles the flow from the pocket 5l. This controlled Wheel power rotated at a constant speed (power connection not shown), discharges a 'constant fixed quantity of sinter. Each cell 59 between paddles lls with sinter at the cut off 55, and is rotated down through the bottom of the pocket and discharged over the edge 55 of the pocket bottom 57. The paddle Wheel can handle material varying greatly in size as the paddles revolve in the sinter and clears by a space the retaining baci; wall 58 and the bottom 5l of the pocket. This paddle wheel 55 is the final controlling part of the stepped sinter machine having a discharge pocket 5i or similar pocketing means. Thefdischarge by this wheel withdraws `and controls the flow of sinter and stock all the way through the machine to the supply above the rgate Il. A discharge conveyor is shown at 5l?. This'control'device` below the table it may be `applied to the embodiment shown in Fig. 2, on .the removal ofy the continuous apron 5B and its operating parts.

The stepped sinter pass (Fig. 5), like the constantslope'sinter pass (Fig. 2) is built into a frame as i9 (Fig. 1), which is supported in the same manner and provides means for the change of slope of the sinter pass. The pivot support of the stepped pass would then be the shaft Si of the pressurey roller '43a (Fig. 5), and the top of vthis stepped pass would be supported by the screw 34 or other similar device (Fig. 1), and chute connections i3, l5, l5, and 25 (Figs. 2 and 5) would be provided. Chute connecting pieces f I3.` i3d, l5 and I6 can be fitted for adjustment, vor can betted and welded for each position of the sinter pass. y

The screw 312 and pivot 25 (or 5l) connect to ithe fixed base having parts 3l, 52 and 33 (Fig. l). All connections (not shown) to the several parts `of this stepped pass are made iiexible'or' e-asily adjusted.

The section (Fig. 6) shows the top pressure and :guide roller 43 with relation to the grate fil, the

air duct 2l' and the sides 24 and shows the chan- .nel 24a; which can be lchanged in depth to'meet changed depth of flow of stock in the sinter pass. :The section (Fig. 7) shows a top pressure roller 143in relation' to a Ariser 45 and grate d2, and

`shows the equalizing gate part 53,`side piecesv 6l! :anddis'charge table filll with the sinter.V pocket 5l,

and the discharge paddle wheel 56 above the bottom wall 51.

The plan at reduced scale of equalizingfgate (Fig. 8) shows the construction of the gate and its location at the bottom-of the sinter pass 44a ywith reference to the sinter pass sides 54.

The air seal provision at the air tight feeding chute l@ and it (Fig. 5) and the discharge pocket 5l provides an opportunity to use a forced draft through the sinter stock in the sinter pass instead of an air suction through the air duct 2l. This can bedone by making a plenum chamber with Walls lil in the room in which the sinter machine is located. i

This plenum chambercan be applied to the embodimentcf Fig-2, as shown by the lines 1,0.

To put the gravit;7 flow sintering machine into operation, fill the machine with sinter stock by opening the stock gate il at the top, start the ignition flame and connect the air and power lines. Any stock going through the machine without being converted to sinter is separated from the sinterv and returned to the stock processing line. Partial loss of fire or ignition does not stop the process as the stock and sinter both pass through theV machine at the same velocity, thus allowing a pick up in ignition. However, the controlling machinery must run and the ignition flame and air pressure must be maintainedlto vproduce a continuous output of sinter.

Many of the sintering plants are very dusty in their operation and reduire elaborate dust collecting equipment. This gravity iiow sintering machine produces relatively very little `dust to be collected as the free now-of the dusty sinter is very limited.

Divisional applications have been led for matter'disclosed herein but not claimed herein. as follows: Serial No. 191,050, Serial No.l 191,051, both iiled on October 19, 1950.

I wish it to be understood that I do not desire to be limitedto the exact details of construction shown and described, for obvious modincations will occur to a person skilled in the art.

1 claim:

1. In al sintering machine, the combination of a sinter pass chute having parallel front and rear walls and inolosing side walls, said front walls consisting of a series of perforated Asteps being `inclined to the vertical, each step inline with the sinter pass chute and lower than its preceding step, said inclination being suchas to retardk but not prevent the now through the sinter pass chute of the stock and sinter` under gravity action, said rear wall consisting of a series of perforated stepped plates, and powered pressure rollers between said perforated stepped plates, whereby said combination of front wall steps, rear wall stepped plates and powered pressure rollers, shears and breaks into pieces the sinter and sinter stock as it flows oif each step downwardly in the `sinter pass chute.

ing end, said front wall being inclined to the y vertical, said inclination being such as to retard but not prevent the flow of the stock under gravity action, said sinterV pass chute having vmeans incorporated with said chute .forbreaking the sinter, an equalizingfgate valve having anv opening below the sinter pass chute for receiving the broken sinter, and means horizontally shifting said'gate valve tobring .its opening in a position in relation to the sinter pass chute to determine the direction of flow of the broken sinter from the sinter pass through the said gate valve opening and thereby the descent in uniform cross-sectional mass ilow of the stock and sinter in the sinter pass chute providing a uni- -form mass flow through the whole cross-sectional area of the sinter pass.

3. In a sintering machine, the combination of a sinter pass chute having parallel front and rear walls and enclosing side walls and an open upper receiving end and an open lower discharging end, said front wall being inclined to the vertical, said inclination being such as to retard but `not prevent the flow of the stock under gravity action, -said chute having sinter breaking means within the sinter pass chute, an equalizing controlled gate valve having an opening below the sinter pass chute discharge for receiving the broken sinter, means horizontally shifting said gate valve to bring its opening to a position in relation to the sinter pass to determine the direction of llow of the broken sinter through the said gate opening, a sinter pocket, below said opening, and a controlled discharge paddle wheel having paddles below the said sinter pocket, providing a uniform flow through the whole cross-section of said sinter pass.

4. In a sintering machine, the combination of a sinter pass chute having parallel front and rear walls and enclosing sidewalls and an open upper receiving end and an open lower discharging end,

said front wall being inclined to the vertical,

said inclination being such as to retard but not prevent the flow of the stock under gravity action, sinter breaking means within the sinter pass chute, and a controlled paddle wheel below the lower end of said sinter pass chute intercepting the broken sinter with its paddles, to determine the rate of ow of the broken sinter through the said discharge opening, and thereby the rate of descent of the stock and sinter in the sinter pass chute.

5. In a sintering machine, the combination of a sinter pass chute having parallel front and rear walls and enclosing sidewalls and an open upper receiving end and an open lower discharging' end, said front wall being inclined to the vertical, said inclination being such as to retard but not prevent the flow of the stock under gravity action, the lower end of said chute having a discharge, means within said chute for breaking the sinter, a horizontal discharge floor, below said discharge of said chute, -said floor having ari-opening, and an adjustable horizontal equalizing gate above said opening in the discharge floor, whereby the discharge ilow of sinter through the gate opening is S positioned as to give the discharging sinter in the sinter pass chute a uniform flow across its cross-section from its lfront wall to the rear wall.

6. In a sintering machinathe combination of a sinter pass chute having parallel front and rear walls and enclosing side walls and an open upper receiving end and an open lower discharging end, said front wall being inclined to vertical, said inclination being such as to retard but not prevent the now of the stock under gravity action, the lower end of said chute having a discharge opening, means within said chute for breaking the sinter, an adjustable horizontal shifting discharge gate having an opening below said chute discharge opening, a horizontal gate supporting discharge floor with a sinter flow opening in said floor below the gate said gate opening and said sinter flow floor opening substantially coinciding, a sinter pocket below the coinciding openings in the said gate and the said floor, and a controlled rotating sinter flow controlling paddle Wheel in said `sinter pocket, whereby the flow of sinter through the gate is at the same rate as the machine produces sinter.

7. In a sintering machine, the combination of a sinter pass chute having sidewalls, with an upper stock receivingend and a lower sinter discharge end, `and having sinter breaking means within the sinter pass for breaking the sinter within the sinter pass, for discharge at the lower end of said chute, a discharge floor having a discharge opening extending from sidewall to sidewall of the sinter pass chute, said floor supporting said sidewalls, an equalizing gate consisting of a rectangular frame formed of two end pieces placed on the floor adjacent to -said sidewalls and outside of same, and of two side pieces connecting the two end pieces locatedl without the discharge opening on said discharge floor, a rst gate leaf connected to one side piece extending between the two sinter pass chute sidewalls and extending toward the opposite side piece, a second opposite gate leaf connected to the opposite side piece, said second gate leaf extending between the two sinter pass chute sidewalls and extending toward the opposite rst gate leai and spaced therefrom, said space between gate leaves being adjustable by screw connection between said second gate leaf and adjacent side piece of said frame; said equalizing gate with all of said frame and leaf parts resting on the discharge floor.

8. In a sintering machine, the combination of` a sinter pass chute having parallel front and rear walls and enclosing sidewalls and an open upper receiving end and an open lower discharging end, said front wall being inclinedto the vertical, said inclination being such as to retard but not prevent the ow of the stock under gravity action, with a series of steps in the front wall of the sinter pass chute, having risers between adjacent steps, a series of sinter pressure rollers in the rear wall of the sinter pass chute, said steps in the front wall of the sinter pass chute being so connected at each riser to form a continuous wall, a series of stepped plates, in the rear wall of said sinter pass chute said plates in the rear wall being separated by said pressure rollers, the rear plates being parallel to the steps in the front wall and at substantially the same spacing from steps in the front wall, with the inclination of the front and rear wall such that the force of gravity acting on the stock and sinter will exceed the combined resistance forces due to action on the front and rear walls, and that of the rollers.

WALTER KELSEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

